Lock opener



INVENTOF? CONRAD H. GREBE ATTORNEY 2 Sheets-Sheet 1 C H GREBE LOCK OPENER Flled March 15, 1943 Nov.16 1943.

Nov.l6,1943. GREBE 2,334,407

LOCK OPENER Filed March 15. 1943 2 sheFats'shee" 2 //v vE/v TOR CONRAD H. 6/?EBE A TTORNE'Y Patented Nov. 16, 1943 "110st QFENEK p T12 cla m (Cruse- 54) The present. invention relates ,tosheehmtal working devicesi'. andv more; particularly to; ma-t chines for opening;v the. pocket; 0L aa-seam. 10.91;; formed on the. edge of; asheet metal-imemberzi This: application: isv a c.ontin11'atisJni-inepButt;v 0t the parent application; Serialza'bhimber 366,432; filed November i3; 1940;: entitled Beckiopeners;

For seaming. together apair" of; sheet. metal pieces; theiedgeiportions thereof! are usually pres formed. or folded in a; suitable: manner; so: that may be hammered together; forming an. interlocking 'seamz firmly uniting the two; members. Machines. haveibeen devised fer; bending or folds.

ing the edges: of::the:sheet nietals'membersrtoebe I thus secured together?but: such.-;machine's 'carr handle-."sheet. metal pieces; only; lathe flat. condition.. In the fabrication:of'irregularzshapesg such:

smoothly ltogether, fer fci' m smooth, tight. seam: and: a: properly squared. corner.

It 15394111; object; of the present nvention there;

iore to provide anew: and-imprcved machine; ior opening quickly andeificientlythe closed.

' pocket, of agprefor med seam; lock provided--cn' as duct elbows in which the throat and heel plates must be curved; the edges of" these plates must be folded before theyla-re givenithetrequisitra' curvature; In. curving these plates, as' bypassing them through a roller type; bendingwmachine, the folded edge portions. are.v more or less flat tened outyclosing the lock pockets. Obviously; before the various parts. can. be assembled-,: the

lock pockets mustilbe-reopenedb Such; closureof the lock pockets during the bending: operation may be prevented by. inserting therein'filler strips for restricting the deformation of the .pocketside walls by the bending machine. rollers and, after the plates have. been curved; removing the filler strips. A disadvantage of this method-bimocedure isthat it is necessary tbaprovide a separate strips cannot .generallybe used a: second time.

This is.duetothefactthatit is clamped so tightly in the; pocket duringi-the; rolling operationthat it: isv usually mutilatedbbeyond iurther; usability,- by the removal process:- requiredv for inserting: the, filler strips'dnto the pockets and removing; thestrips'therefrom; following the. rolling operaticmplus, the. costiof the filler strips'themselves, addsr ve fy materially to the total cost of; making; seams by this m th d.

the ceeneratine a a o b m ete fit The amount of time. l

. theedge of as sheet metalmember;

A further object of the invention istoprovide a new and improved sheet .metala seam lock opera ingmachine which comprises relatively few parts when assembled the: overlapping: edge portions I rwhich c adapted-t enga e wit an i lvfi mre t rou h. mac n a she t metal; piecehaving aiiolded; seam 106K011 the edge thereof. 1 'I-he :sheet metalgpieceris so fedthrough,

he: ch n hat-th ed e rave s bs a tially straight: lige -The; machinegalsqz includes. an; arrangement 0.? tool elements; which a re lated to ene eewit ithes di ee sero fi en i. t l k and stra h en intor rall li alienemnw hesheetbmly w le line of: e t o elements dependsg'downwardly into: the lock pocket to; wedge the'foIded-wall'i'portion of the" lock "outwardly intoiarpredetermined; spaced? rela ticn with; respect to the standing" edge portion.

Further modificationsand" advantages of the invention willbe described in the following specifi'catio'n, while the ieatures otnovelty will be pointed out with greater particularity in the appendedc'la'ims. I v

Referring'tethe drawings, Fig. 1" is a side elevatiori fof thesheet' metal-f 'seam lock joperiing machinecoiistructedin aecordance with one form of the in entio Fig-Q 2 rs anend'view' ;of t e machine illustrated Fig. 1'; Fig.- 3 is"a "f;ragmentary View illustrating operational features of certain v details of the machineshowrifin Fig.1 1,; Fig. fliS a side elevation of a machine constructed in accord'a nj ce' with a modification of the inven the; st: a enlar ed v w'u n perspective of one detailof the machine shown in Hi h-4,; Fig, 6 is a iragmentary view illustratingafurther modification, of the invention; Fig, .7f is ai view in perspective. of. a sheet. metal. conduit elbow having. hammered lock seams at the corners thereof; Figs. 8, 9 and. 10 are explanatorydia grammatic views,i11u strati ng in. enlarged detail a typical hammeredlock as} used ,in-sheet metal dueticonstruction.

ordeh that the tunction of l the .inyention may mere clearly be understood;

the attention is first directed to the explanatory views of Figs. 7 to .10, inclusive. In Fig. 7 is shown'a sheet metal duct elbow, of more or less standard construction, comprised of top and bottom plates. l and II and heel and throat Plates l2 and I3, respectively. The various plates are secured together by folded seams extending along the corners of the assembly, the particular seam shown in this instance being of the well known hammered or Pittsburglock type. The details of this type of lock areshown more'clearly in the views of Figs. 8 and 9. .In the formation of this look the heel and throat plates l2 and I3 are foldedalong their opposite edges while in a flattened condition, either by means of a brake or other suitable sheet metal bending machine, so as" to provide an offset folded wall portion l4. and a upper end of a conventional-bench bracket a is indicated at 34 in Fig. 4. For this'p'urpose the lower end of the leg 3| is provided with a'cylindrical portion 35 which is adapted to be cooper-1 atively received in the socket 36 provided in the upper end of the bracket 34 and be secured therein by any suitable means such as set screw 37. The lower end of the bracket 34 is provided with a suitabl clamp 38 for fastening ontothe edge P rtion39 ofa work bench. 7

The machine as described and illustrated is in the general form of an inverted U, the two legs of which are loosely connected together at their upper. ends. The lower or free ends of the legs and 3| are provided with feed rolls 4i! and 4!,

respectivelmwhich are journaled between corresponding pairs of inwardly extending bosses 42,

standing edge portion l5 defining pocket Hi there- 3 between. In a properly formed lock of'this type the standing edge portion l5 extends in the same plane as the body I 1 of the sheet, while the offset foldedwall portion 'l4 extends substantially parallel to the edge The top and bottom plates I0 and H are provided at their opposite edges with flanges l8 bent at right angles to the body portions I 9, which flanges are adapted to be cooperatively fitted into thepockets Hi. The sheet metal members l1 and lfl'arelocked securely together "by hammering over-the uppermost edge of the standing portion l5 in the manner'as indicated at 15' in Fig. 9; If the edges of the sheets are initially properly bent, th sheets may then readily' be' assembled and seamed toether to form straight duct sections. However,

.in manufacturing curved duct sections such 'as'is illustrated-by the elbow' shown' in Fig.'7;-the heel and throat plates must first be curved, which I operation deforms the'locks' as-initially prepared so as to make it impossibleto assemble the various pieces without first reshaping'the lock.-

The deformation of locks in-the curving operation is fdue to thefact thjat in'passing th plates 'through'the rolling machine the roll on' one side of the plate bear only-against the folded wall portion l4 of the lock which projects above the surface of the'plate body. 'r'I'his results in the bend ingfofthe wall and edge portion l4 and |5 towards each' other;.and hence the closing of the lock pocket I Gin the manner illustrated in Fig. 10. It will be obvious that beforethe top andbottom 'plates -lo'andll can be assembled into the pockets of the throatand heel plates the lock must be reformed, that is, notonly merely opening' the; pocket I6, but also straightening the standing edge portion=l5 and the folded wall portion l4 into their initially formedcondition. It is for accomplishing this result that the machine of the inventionfinds' its greatest usefulness. 1

1 While the machine of the present inventionIis particularly suitable for opening closed or partially closed. pockets of seam locks of the type 43 and 44, 45 formed integrally with the lower portions of the respective frame legs. Th feed rolls and 4| are arranged axially parallel, extending in the direction of the frame legs. 'cfland 3| Theroller 40 is an idler, while roller 41- is a driverg'itbeing provided with a gear 46 intermediate its ends and which gear is of a diameter somewhat less than the opposite end portions;

which end portions areknurle'd in order to pro-' vide for suitable frictional engagement with .the sheet metal piece to be'fed thereby; The gear is meshed with a right angularly arranged gear '41 attached to one end of a driving shaft '48.

The driving shaft48 is journaled 'within a hub portion49 formed integrally with-th lower end of the frame leg 3!, while the outer end of the shaft 48 is provided with a crankhandle 5! bymean of which. rotation of' the drivin roll 4| may .be-.. efiected. As will'subse'quently. be described,however, thev driving forc may be supplied.bt suitablemotor means connected to the a end Of the shaft48. e

By. virtue of the loose connection. between upper endsof the frame legs, .theyma'y be moved' laterally apart=to permit the insertion of a sheet showninFigslfl. to l0,.it will become obvious as the-description thereof proceeds that the machine of the invention is not. necessarily solimited in its field of'applicationf. 5'.

Themachine as shown in the drawings com-' prises a frame having two leg' portions 39 and 3|, which are looselyconnected together at their upper ends by .means of. a through bolt 32. The. opening through the upper end of one "of the frame legs-for receiving the bolt 3 2 is slightly elongate in the transverse direction, as indicated at 33, so as to allow limited transverse movement between the frame legs 30 and 3|. I The frame is adapted to be fixedly supportedas upon. the

metalpiece,-as indicated at 53, between thefeed rolls;'40 and 4|; with the upper edge of thesheet metal 'piece extending be'yond the upper endsof. the rolls and substantiallyat right angles. with respectthereto. The frame legs Siland 3!. are further adapted to be 'shifteditoward each other so "as to'bring therolls 40 and 4! into clamping engagement with the opposite sides of. the sheet metal piece 53 to hold it securely in place. A rod 7 55 is rigidly securedat .one end to one of the frame'legs, such as 3|, extends at right angles betweentwo framelegs, and through a cooperat ing' opening provided in the opposite leg 33. The a twoleg's 3E! and 3|" are normally urged apartby me'ans of a biasing compression spring 56arrangedabout'the rod 55 between a stop collar 51 and the adjacent innersurface of leg 30. Any

suitable means are provided on the outermost 58 and 59 are provided with cooperating sloping. cam" surfaces 5 3and--64,"respectively, whereby, upon rotationalmovement of the outer disc'59 by handle- 62, an inward thrust is imposed upon 7 the surfaces 53; and 64: is: such that mm!- ment; of the handle 612i throughan anglefofxapproximat'ely 180E degreesxwillz'efiect mdvemmt. ot the frame legs between their lithitposittoms:

The slope of the surfaces 63 and 64 is alsnfsuch that the frictional resistance theize'between will prevent automatic: separationl ot the legs M and 31 and when once sheet piece such as 53. is clamped. between: the feeding: rolls MI and H. I

The tool means provided for eitectin-g the opening of the seam lock according to the: first modification of the invention cenipri'se's, a pair of similar relatively discs HI and M niQUnted for free rotation upon. am otfsetiend portion l2 of a shaft"- I 3 The disc si'TlF and: El are prererably provided with oppositely extending hub portions F4 and .15, providing enlarged beai 'ing surfaces therefor respect'to the shafit portion if. The discs FB-andi'lf arepi'eferably of hardened steel, relatively thin at their edges; and beveled outwardly toward tli eir centers to: a thickness somewhat greater than at their edges Preferably, the angle of "bevel is somewhat and-flit the upper: extremity or the standing edge 7 will be: therebetween; Because of the. fact that theistanding edge: will be' varioushrr deformed negard t its 'alfgm'nent the: main body of the: piece.- 53', the supporting shaft fi for the. disc tools may belongitudihal'ly. adjusted through the frame-L leg II: as necessary as: the" discs l'fl 'andl H- are lowered. Following initial entry or the upper edge oi the. sheet metals. piece: between the discs, Ill. and H, acontihued force applied to the handle- 84- will force the discs Tll an'd. H- downwardly until one of the-disc's reaches. thebottom ofthe pocket, 'alsoiforcing the: standing edge portion; of the look: into agparall'el; alignment with the h andsismultaneously wedging; thefolded: wall poi'tion'. of"; the. lock outwardly into the proper spaced relation. with. respect. to the standing' edge. portion, Preferab1y,. the, angle of bevel om the outer side: of the di'scsis suchthat when greater on the hubs side's of the discsithan on 1 the face sides substantially-as illustrated the fragmentary enlarged View of Fig} "3 The discs IB- and H may be biased towards each other by means of a compression spring 1G arranged about the outer end of the shaft portion 12 between the stop washer IT and nut [8.

The.

outer end of the shaft portion?! is provided with a flattened side and washer 1 with a teoperatively shaped opening so as to-prevent'rtm tion of the disc hub 14' from; automatically unscrewing the nut 18. By adjusting the nut-1B, the degree of separationbetween discs} F0 and H can be controlled for different weights of metal. f

The shaft portion [2 supporting the disc's M and H is secured 'eccentri'cally ontothe endoi the shaft portion 13 whichis jburnaled within a cooperating bore" provided through the frame leg 31. Mounted on the outer end of thesha-ft i3 is a manual adjusting'handle 81 by" means of which the shaft 1-3" may be rotated forraising or lowering-.discsl-fl and H with relation to the edge of the sheet metal piececlamped between the" feed rolls 4U andl ll The shaft 13,1in

addition to being freely rotatable within the frame leg 3 l isalso longitudinallyslidable the're through. in order to facilitate the adjustment of the disc tools. into theoperative position with respect to" the standing edge of the sheet metal seam lock. The shaft T3 includesan' enlarged portion 82 between the shaft: portions Hand [3 providing shoulders 83 and. on the opposite ends thereof. The shoulder '83 provides a thrust bearing surface for. the hub. 15 of thedisc tool TI, while shoulder 84 provides a stop for. limiting axial movement of the shaft l3 through the frame leg 3| to theright, asviewed in Fig. 1. I

In Fig. 3- the disc tools 10 and 11' are shown. in the elevated position, in which positionfthey are placed during the clamping'of the sheetmetal member 53 between the feed rolls El! and Ail. To lower the disc tools"! and H to the. operative position, the handle M is rotated in the proper di= rection, counterclockwise as viewed in the end view of Fig. 2". Because of the bevel of-the'fac ing surfaces ofthe disc tools, the peripheraledges thereof are spaced apart a. distance somewhat greater than the thickness of themetafofthe piece 53, so that upon lowering" of the discs 10 one otithe". discs, asa'lllg. forced downwardlt to the bottom of therpocket, the:- folded' wall portion 'allel spacedzrelationrtherewith. With the disc tools 10 and H lowered to? the'operative position as illustratedin'Fig. 1,. the. sheet metal piece 53 7 may be: fed through. the" machine by rotation of the. hamct crank 51:; The disc.- tools. 10' and H will be retained theirlowered position as the sheet metal member isfed through the machine by; virtue of the fact that the forceapplied thereagainst isin the reverse direction of'rotation withrespect to the supporting shaft 1:31 to that required? for effecting: upward movement of these discs.- In order to limit. downward movement of. thedisc toolsliil and? I la to: the; depth: of the pocketv in the sheet metal-L member 53; a screw 8-5ais provided. in the handle; 81:, the. lower'end; of which is adapted to, butti againstra stop &61 provided; on the; outer side-wallofthe frame legf3 I asshown more clean ly'instheaendviewof Fig.2; i Fcrguiding-thenmvem'ent.otthe upper edge of the sheet: metal piecesiitthrough the machine in a predetermined straight: line a. pair of. guides, or gauges;. 8:1- and: 8-8 mounted in: bosses 89' and 90 on the opposite sides of the. frame 'leg 31: extend acrossthet front and rear sides-of themaohine in parallet horizontal alignmentwiththeupper edge of the sheet metal. piece 53.. These gauges may be adjusted. by means of suitable set screws provided: the bosses 89 and 99; respectively;

disc: tools [0? and: H are readily removable from the end of the shaft portion I2 by simply removingthenut-lsg.spring: 15;.an'd washer 11 for replacement with otherrt'ools. or difieren t sizes. as may required, depending upon the particular weight of metal being worked uportor curvature or the sheet. A seconds-tyl'e of toolswill' presently he described.

once the discs m andl-l are-shifted to the 0pei'ati ve' position as shown Fig. the sheet metat piece 53 may be fed through the machine at a relatively high rate of speed, whereupon the sears lockii's made iii-readiness for assembling into the final structure. The standing edge-portion is straightened out smoothly and in: parallel alignmentwith the main body of" the-sheet metal piece, and the folded wall portion is wedged out into a substantially parallel spaced relation with re spect' to the standing edge; 7 It will he -noted that while the disc III-act'sas" a wedgefor epening'tl ie lock pocket, it also acts as an ironerto smoothen the standihg" edge against the cooperating. backingdlsc 1 1-. "while it not essential it'j is preferried that the discsw a-rid' 'fl be (if-substantially discs 10am II. V is shown more clearly in the enlarged perspective 'identical size and shape sothat'rit will be imma terial as.to the particular-directionin which the sheet metal piece is. passed through the machine. In other words, looking at Fig. 1, it is immaterial whether the foldedwallportion of the lock'seam' edge extendsjtothe left of the disc mm-to the right of the disc II Thisis of importance particularly whendealing with curved heel'and throat plates such as were referred to in connection with Fig.7, which, it :will be observed',iwhile being curvedin the same direction, have oppositelydisposedilocks formedon the opposite edgesithereof.

Referring now more particularly to the modification illustrated in Figs, 4- and 5,:the' structure therein shown is substantiallysimilar to that previously described, with the exception 'that the rotarytypetools l and II, as previouslydescribed have been substituted by non'rotatable, blade type tools; J Referring to Fig. 4, the seam lock-reforming toolsin this instance comprise a pair of similarly formed; elements I GI and". I52 which are mounted upon thelofiset shaft'portioii'li of the shaft 73 'inlsubstantiallythe samemanner as the One of the similar toolelements view of Fig. 5. Each tool .comprises fameritral body portion I333 having, an opening lfi -iwthere throughfor cooperatively mountingupon the offset shaft portion 'IZ'of the machine,v iDepending from the lower end of the central body portion I63 and adjacentjone side thereof is a relatively thin 1 tip portion I85 resembling a .blunt' chisel having rounded corners .and with rounded "taper'ed sides. The opposite sides of the tip portion I05. are tapered so that the .central vertical cross hand lever "I I 4 pivoted as at H5 onto a bracket arm H6 extending outwardly from the adjacent frameleg 3 I It will be obvious that any suitable connection andcontrol arrangement therefor may be provided between the motor and the driven machine. .7 f

Having described the principle of'the machine of. the invention'in what are. considered to be operative embodimentsthereof, it is desired that it be understoodthatthevarious specific details shown are merely illustrative, and that theinvention may be carried out in other ways.

'I'oIaimI, 1. In a device for opening a lock seam on the I edge ofa sheet metal member, said device comprising a, pair of relativelymovable jaws, .means for fixedly supporting afirsi; of said jaws, means for supporting the second of said jaws on said first jaw in a generally parallel aligned relation with respect to saidfirstijaw, axially parallel rollersujournaled in corresponding free ends of said jaws, the axes of said rollers extending longitudinally of said jaws, saidrollers being adapted v toengage flatwisewith each of the opposite sides of a sheet metalmember, means for driving one of said rollersfor feedingsaid sheet metal mem- 7 her between said; rollerswith'the seamed edge of said member extending beyond the upper ends of said rollers and substantiallyat right angles with respect to the axes of said rollers, means adjust- Q ably secured to one'of said jaws and, independent section is of substantially the same dimensions'as the radial section of one of the-discv toolsas previously described. --'Ihe upper end ofthe'tool I0! is bifurcated in the transverseplaneidefiningtwo fingers I06 and III"! of such a length as'to'exten'd upwardly on' opposite sides 'ofthe transverse rod arranged between the frame legs 3iii-and 3E. The slot between the fingers I06 and I Ellis suff ciently long so as to permit of free up and down movementof the tools in response to movement of the adjusting handleBIQ.

V The forming tool's' IilI and I 62 of'thismodifi cation are particularly suitable for use in connection with sheet metal pieces which have been curved with a relatively short radius.- It will be understood that the rotary disc typ tools-such as T9 and II, as previously described, are relatively wide; across their mid section and for this'reason cannot negotiate-short radius turns of the seam lock-without causing anexcessive opening of the I lock pocket. On-the, other hand, i the .tips I85 of the stationary type tools Ii] I, I02. are relatively narrow in width so thattheseam'lock pocket will be opened only to the requisite degreeeven in theevent of a short radius of curvature of the sheetmetal piece being worked upon. In other respects, the mode of manipulation and function of the tools embodied in this modification of the invention are substantially the same as' previously described. 7. I

. As previouslymentioned, the machine of the invention may be connected for operationthrough a suitable prime mover such as an electric motor, one such driving arrangement being illustrated I in the fragmentary shetch of Fig. 6. In this inbe controlled by, any suitable means such as a of the other-of said jaws for extending downwardly into the pocket of the lock seam on the edge of said sheet metal member for opening said lock seamI pocket as said sheet metal member is fed between said rollers.

2. In a device for opening a lock seam on the edge of a sheet metal member, comprising a generally; U-shaped frame including a pair of relatively movable leg portions loosely connected together at one end, means for adjusting said leg portions toward eachother, a pair of axially parallel rollers journaled in the respective outer ends of said leg portions, the axes of said rollers extending-longitudinally of said leg portions, said rollers being adaptedto be moved by said adjusting means'into engagement with correspondingopposite, sides of a sheet metal member inserted therebetween, means for driving one of said rollers whereby said sheet metal member may be fed betweensaid rollers with the seam edge of said member extending beyond the end of said rollers in a line at right angles with respect to theaxes of said sheet metal memberwhereby said wedging member opens said lock seam pocket as said sheet metal member is fed between said rollers.

3. Inamachine for opening the pocket of a seam lock on the edge of a sheet metal member, the combination comprising a frame, a pair of feed rollsfor feeding through said machine said sheet metal member, a pair of relatively thin disc members for engaging with each of the opposite sides of the standing edge of the lock, one of said discs being adapted for extending'into the said pocket for effecting the opening thereof, a shaft having an offset portion, said discs mounted coaxiallyfor free rotation on said ofiset shaft por-. tion, said shaft being journaled in said frame for rotational and longitudinal sliding movement therein, and control means attached to said shaft for effecting adjustment of said discs relative to said sheet metal member,

4. In 'a-sheet metal lock opening machine, the combination comprising a frame, a pair'of feed rolls for feeding through-said machine a sheet metal member havinga pr'eformed lock edge, a pair or relatively flat pointed 'tool elements for engaging with each of the oppositesides -of the standing edge 'of th'e'lock, one of said tool elements being adapted to extend into the lock pocket substantially the full depth thereof for effecting the opening of said pocket, a shaft journaled in said frame, said tools being eccentrically supported on said shaft whereby said tools may be shifted toward and away from said sheet metal member, and means for maintaining said tools in a predetermined aligned position as regards the path of movement of said sheet metal member through said machine.

5. In a sheet metal seam lock opening machine, the combination comprising a frame, a pair of feed rolls for feeding through said machine a sheet metal member having a seam lock formed on the edge thereof, said sheet metal member being adapted to be fed through said machine so that said edge travels along a predetermined straight line at right angles to the axes of said rolls, a pair of similar relatively thin disc tools for engaging each of the opposite sides of the standing edge of the seam lock, means on said frame supporting said discs coaxially, the plane of said discs extending parallel with the plane of the sheet metal portion between said rolls, said discs having relatively thin edges and outwardly beveled opposite faces.

6. In a machine for opening the pocket of a seam lock on the edge of a sheet metal member, the combination comprising a frame, means for feeding said sheet metal member through said machine, gauge means on said frame for guiding the edge of said sheet metal member along a predetermined line, means on said frame for cooperatively engaging with each of the'opposite sides of the standing edge portion of the seam lock, said means including means for depending downwardly into the seam lock pocket for simultaneously straightening said standing edge portion into substantial parallel alignment with the sheet metal piece body and wedging outwardly the folded Wall portion of the lock into a predetermined spaced relation from said standing edge portion as said sheet metal piece is fed through said machine.

7. In a machine for opening the pocket of a seam lock on the edge of a sheet metal member, the combination comprising a frame, means on said frame for feeding said sheet metal member through said machine, means on said frame for guiding the lock edge of said member along a predetermined fixed line, means mounted on said frame on the opposite side of said fixed line with respect to said member for movement into cooperative engagement with the edge of said sheet metal member, said last mentioned means including a pair of tool elements for engaging with each of the opposite sides of the standing edge portion of the seam lock, one of said elements having a relatively thin tip portion for extending downwardly into the seam lock pocket, said tool elements simultaneously straightening said standing edge portion into substantial parallel alignment with the main body of said sheet metal piece and wedging the folded wall portion of the lock outwardly into a predetermined spaced relation from said standing edge portion as said sheet metal piece is fed through said machine.

8. In a machine for opening the pocket of a said frame for moving said disc tool elements into cooperative engagement with the standing edge portion of said lock, one of said disc tool elements depending into the lock pocket for simultaneously wedging the folded wall lock portion into a predetermined spaced relation from the standing edge lock portion.

9. Ina machine for opening the pocket of a seam lock on the edge of a sheet metal member, the combination comprising a frame, means on said frame for feeding said sheet metal member through said machine, means on said frame for guiding the lock edge of said member along a predetermined line, a pair of disc tool elements mounted on said frame on the opposite side of said line with respect to said sheet metal memher, said disc tool elements being mounted parallel with said sheet metal member, means for adjusting said disc tool elements into cooperative engagement with the seam lock on said member, the facing surfaces of said disc tool elements being beveled whereby the peripheral edges thereof are spaced apart for facilitating straddling of the standing edge portion of the seam look by said disc tool elements.

10. In a machine for opening the seam lock on the edge of a sheet metal member, the combination comprising a frame, means for feeding said sheet metal member through said machine, means for guiding the seam lock edge of said sheet metal member along a predetermined line, a pair of tool elements mounted on said frame and adapted to be adjusted into cooperative engagement with the seam lock on said member, said tool elements having relatively thin extremities and having facing surfaces tapering outwardly whereby said extremities are spaced apart for facilitating straddling of the standing edge portion of the seam look by said tool elements, one of said tool elements adapted for depending downwardly into the lock pocket for effecting the opening thereof as said sheet metal member is fed through said machine.

11. In a machine for opening the pocket of a seam lock on the edge of a sheet metal member, the combination comprising a frame, a pair of feed rolls for feeding through said machine said sheet metal member, a pair of relatively thin disc members for engaging with each of the opposite sides of the standing edge of the lock, one of said discs being adapted for extending into the said pocket for effecting the opening thereof, a shaft having an offset portion, said discs mounted coaxially for free rotation on said offset shaft portion, spring means on said shaft portion resiliently biasing said discs toward each other, said shaft being journaled in said frame for rotational and longitudinal sliding movement therein, and control means attached to said shaft for effecting adjustment of said discs relative to said sheet metal member.

12. In a sheet metal lock opening machine, the combination comprising a frame, a pair of feed rolls for feeding through said machine a sheet metal member having a preformed lock edge, a pair of relatively flat pointed tool elements for engaging with each of the oppositesides of the ward and away from said sheet metal :member, standing edge of the lock, one of said tool elements spring means on;-said shaft resiliently biasing said being adapted to extend intotthe lock pocket subtools together, and means for maintaining said stantially the full depth thereof forefi'ecting the tools in ga-predetermined aligned position as reopening of said pocket,'a shaft journaled in said 5 gards the path of movement of said sheet metal frame, said tools being eccentrically supported on memberthroughsaid machine. said shaft whereby said tools may bevshifted toe z CONRAD H; GREBE. 

